-- package provides a basic tree structure. Sinfo describes how this structure
-- is used to represent the syntax of an Ada program.
--- The grammar in the RM is followed very closely in the tree
--- design, and is repeated as part of this source file.
+-- The grammar in the RM is followed very closely in the tree design, and is
+-- repeated as part of this source file.
-- The tree contains not only the full syntactic representation of the
-- program, but also the results of semantic analysis. In particular, the
-- Comes_From_Extended_Return_Statement (Flag18-Sem)
-- Present in N_Simple_Return_Statement nodes. True if this node was
-- constructed as part of the N_Extended_Return_Statement expansion.
- -- .
-- Compile_Time_Known_Aggregate (Flag18-Sem)
-- Present in N_Aggregate nodes. Set for aggregates which can be fully
-- Sem_Aggr for the specific conditions under which an aggregate has this
-- flag set. See also the flag Static_Processing_OK.
+ -- Componentwise_Assignment (Flag14-Sem)
+ -- Present in N_Assignment_Statement nodes. Set for a record assignment
+ -- where all that needs doing is to expand it into component-by-component
+ -- assignments. This is used internally for the case of tagged types with
+ -- rep clauses, where we need to avoid recursion (we don't want to try to
+ -- generate a call to the primitive operation, because this is the case
+ -- where we are compiling the primitive operation). Note that when we are
+ -- expanding component assignments in this case, we never assign the _tag
+ -- field, but we recursively assign components of the parent type.
+
-- Condition_Actions (List3-Sem)
-- This field appears in else-if nodes and in the iteration scheme node
-- for while loops. This field is only used during semantic processing to
-- package Exp_Util, and also the expansion routines for the relevant
-- nodes.
+ -- Context_Pending (Flag16-Sem)
+ -- This field appears in Compilation_Unit nodes, to indicate that the
+ -- context of the unit is being compiled. Used to detect circularities
+ -- that are not otherwise detected by the loading mechanism. Such
+ -- circularities can occur in the presence of limited and non-limited
+ -- with_clauses that mention the same units.
+
-- Controlling_Argument (Node1-Sem)
-- This field is set in procedure and function call nodes if the call
-- is a dispatching call (it is Empty for a non-dispatching call). It
-- scope are chained, and this field is used as the forward pointer for
-- this list. See Einfo for further details.
+ -- Next_Implicit_With (Node3-Sem)
+ -- Present in N_With_Clause. Part of a chain of with_clauses generated
+ -- in rtsfind to indicate implicit dependencies on predefined units. Used
+ -- to prevent multiple with_clauses for the same unit in a given context.
+ -- A postorder traversal of the tree whose nodes are units and whose
+ -- links are with_clauses defines the order in which Inspector must
+ -- examine a compiled unit and its full context. This ordering ensures
+ -- that any subprogram call is examined after the subprogram declartion
+ -- has been seen.
+
-- Next_Named_Actual (Node4-Sem)
-- Present in parameter association node. Set during semantic analysis to
-- point to the next named parameter, where parameters are ordered by
-- Note: the back end places some restrictions on the form of the
-- Expression field. If the object being declared is Atomic, then
-- the Expression may not have the form of an aggregate (since this
- -- might cause the back end to generate separate assignments). It
- -- also cannot be a reference to an object marked as a true constant
- -- (Is_True_Constant flag set), where the object is itself initialized
- -- with an aggregate. If necessary the front end must generate an
- -- extra temporary (with Is_True_Constant set False), and initialize
+ -- might cause the back end to generate separate assignments). In this
+ -- case the front end must generate an extra temporary and initialize
-- this temporary as required (the temporary itself is not atomic).
-- Note: there is not node kind for object definition. Instead, the
-- Aliased_Present (Flag4) set if ALIASED appears
-- Constant_Present (Flag17) set if CONSTANT appears
-- Null_Exclusion_Present (Flag11)
- -- Object_Definition (Node4) subtype indic./array type def./ access def.
+ -- Object_Definition (Node4) subtype indic./array type def./access def.
-- Expression (Node3) (set to Empty if not present)
-- Handler_List_Entry (Node2-Sem)
-- Corresponding_Generic_Association (Node5-Sem)
-- SIMPLE_EXPRESSION [not] in RANGE
-- | SIMPLE_EXPRESSION [not] in SUBTYPE_MARK
- -- Note: although the grammar above allows only a range or a
- -- subtype mark, the parser in fact will accept any simple
- -- expression in place of a subtype mark. This means that the
- -- semantic analyzer must be prepared to deal with, and diagnose
- -- a simple expression other than a name for the right operand.
- -- This simplifies error recovery in the parser.
+ -- Note: although the grammar above allows only a range or a subtype
+ -- mark, the parser in fact will accept any simple expression in place
+ -- of a subtype mark. This means that the semantic analyzer must be able
+ -- to deal with, and diagnose a simple expression other than a name for
+ -- the right operand. This simplifies error recovery in the parser.
+
+ -- If extensions are enabled, the grammar is as follows:
+
+ -- RELATION ::=
+ -- SIMPLE_EXPRESSION [not] in SET_ALTERNATIVE {| SET_ALTERNATIVE}
+
+ -- SET_ALTERNATIVE ::= RANGE | SUBTYPE_MARK
+
+ -- The Alternatives field below is present only if there is more than
+ -- one Set_Alternative present, in which case Right_Opnd is set to
+ -- Empty, and Alternatives contains the list of alternatives. In the
+ -- tree passed to the back end, Alternatives is always No_List, and
+ -- Right_Opnd is set (i.e. the expansion circuitry expands out the
+ -- complex set membership case using simple membership operations).
-- N_In
-- Sloc points to IN
-- Left_Opnd (Node2)
-- Right_Opnd (Node3)
+ -- Alternatives (List4) (set to No_List if only one set alternative)
-- plus fields for expression
-- N_Not_In
-- Sloc points to NOT of NOT IN
-- Left_Opnd (Node2)
-- Right_Opnd (Node3)
+ -- Alternatives (List4) (set to No_List if only one set alternative)
-- plus fields for expression
--------------------
-- Forwards_OK (Flag5-Sem)
-- Backwards_OK (Flag6-Sem)
-- No_Ctrl_Actions (Flag7-Sem)
+ -- Componentwise_Assignment (Flag14-Sem)
-- Note: if a range check is required, then the Do_Range_Check flag
-- is set in the Expression (right hand side), with the check being
-- Note: the back end places some restrictions on the form of the
-- Expression field. If the object being assigned to is Atomic, then
-- the Expression may not have the form of an aggregate (since this
- -- might cause the back end to generate separate assignments). It
- -- also cannot be a reference to an object marked as a true constant
- -- (Is_True_Constant flag set), where the object is itself initialized
- -- with an aggregate. If necessary the front end must generate an
- -- extra temporary (with Is_True_Constant set False), and initialize
+ -- might cause the back end to generate separate assignments). In this
+ -- case the front end must generate an extra temporary and initialize
-- this temporary as required (the temporary itself is not atomic).
-----------------------
-- Has_No_Elaboration_Code (Flag17-Sem)
-- Body_Required (Flag13-Sem) set for spec if body is required
-- Acts_As_Spec (Flag4-Sem) flag for subprogram body with no spec
+ -- Context_Pending (Flag16-Sem)
-- First_Inlined_Subprogram (Node3-Sem)
-- N_Compilation_Unit_Aux
-- N_With_Clause
-- Sloc points to first token of library unit name
-- Name (Node2)
+ -- Next_Implicit_With (Node3-Sem)
-- Library_Unit (Node4-Sem)
-- Corresponding_Spec (Node5-Sem)
-- First_Name (Flag5) (set to True if first name or only one name)
-- reconstructed tree printed by Sprint, and the node descriptions here
-- show this syntax.
+ -- Note: Conditional_Expression is in this section for historical reasons.
+ -- We will move it to its appropriate place when it is officially approved
+ -- as an extension (and then we will know what the exact grammar and place
+ -- in the Reference Manual is!)
+
----------------------------
-- Conditional Expression --
----------------------------
-- No_List in the tree passed to Gigi. These fields are used only
-- for temporary processing purposes in the expander.
- -- Sprint syntax: (if expr then expr else expr)
+ -- The Ada language does not permit conditional expressions, however
+ -- this is under discussion as a possible extension by the ARG, and we
+ -- have implemented a form of this capability in GNAT under control of
+ -- the -gnatX switch. The syntax is:
+
+ -- CONDITIONAL_EXPRESSION ::=
+ -- if EXPRESSION then EXPRESSION
+ -- {elsif EXPRESSION then EXPRESSION}
+ -- [else EXPRESSION]
+
+ -- And we add the additional constructs
+
+ -- PRIMARY ::= ( CONDITIONAL_EXPRESION )
+ -- PRAGMA_ARGUMENT_ASSOCIATION ::= CONDITIONAL_EXPRESSION
+
+ -- Note: if we have (IF x1 THEN x2 ELSIF x3 THEN x4 ELSE x5) then it
+ -- is represented as (IF x1 THEN x2 ELSE (IF x3 THEN x4 ELSE x5)) and
+ -- the Is_Elsif flag is set on the inner conditional expression.
-- N_Conditional_Expression
- -- Sloc points to related node
+ -- Sloc points to IF or ELSIF keyword
-- Expressions (List1)
-- Then_Actions (List2-Sem)
-- Else_Actions (List3-Sem)
+ -- Is_Elsif (Flag13) (set if comes from ELSIF)
-- plus fields for expression
- -- Note: in the case where a debug source file is generated, the Sloc
- -- for this node points to the IF keyword in the Sprint file output.
-
-------------------
-- Expanded_Name --
-------------------
N_In,
N_Not_In,
- -- N_Subexpr, N_Has_Etype
+ -- N_Subexpr, N_Has_Etype, N_Short_Circuit
N_And_Then,
+ N_Or_Else,
+
+ -- N_Subexpr, N_Has_Etype
+
N_Conditional_Expression,
N_Explicit_Dereference,
N_Function_Call,
N_Indexed_Component,
N_Integer_Literal,
N_Null,
- N_Or_Else,
N_Procedure_Call_Statement,
N_Qualified_Expression,
N_At_Clause ..
N_Attribute_Definition_Clause;
+ subtype N_Short_Circuit is Node_Kind range
+ N_And_Then ..
+ N_Or_Else;
+
subtype N_Statement_Other_Than_Procedure_Call is Node_Kind range
N_Abort_Statement ..
N_If_Statement;
function Component_Name
(N : Node_Id) return Node_Id; -- Node1
+ function Componentwise_Assignment
+ (N : Node_Id) return Boolean; -- Flag14
+
function Condition
(N : Node_Id) return Node_Id; -- Node1
function Context_Installed
(N : Node_Id) return Boolean; -- Flag13
+ function Context_Pending
+ (N : Node_Id) return Boolean; -- Flag16
+
function Context_Items
(N : Node_Id) return List_Id; -- List1
function Is_Dynamic_Coextension
(N : Node_Id) return Boolean; -- Flag18
+ function Is_Elsif
+ (N : Node_Id) return Boolean; -- Flag13
+
function Is_Entry_Barrier_Function
(N : Node_Id) return Boolean; -- Flag8
function Next_Entity
(N : Node_Id) return Node_Id; -- Node2
+ function Next_Implicit_With
+ (N : Node_Id) return Node_Id; -- Node3
+
function Next_Named_Actual
(N : Node_Id) return Node_Id; -- Node4
procedure Set_Component_Name
(N : Node_Id; Val : Node_Id); -- Node1
+ procedure Set_Componentwise_Assignment
+ (N : Node_Id; Val : Boolean := True); -- Flag14
+
procedure Set_Condition
(N : Node_Id; Val : Node_Id); -- Node1
procedure Set_Context_Items
(N : Node_Id; Val : List_Id); -- List1
+ procedure Set_Context_Pending
+ (N : Node_Id; Val : Boolean := True); -- Flag16
+
procedure Set_Controlling_Argument
(N : Node_Id; Val : Node_Id); -- Node1
procedure Set_Is_Dynamic_Coextension
(N : Node_Id; Val : Boolean := True); -- Flag18
+ procedure Set_Is_Elsif
+ (N : Node_Id; Val : Boolean := True); -- Flag13
+
procedure Set_Is_Entry_Barrier_Function
(N : Node_Id; Val : Boolean := True); -- Flag8
procedure Set_Next_Entity
(N : Node_Id; Val : Node_Id); -- Node2
+ procedure Set_Next_Implicit_With
+ (N : Node_Id; Val : Node_Id); -- Node3
+
procedure Set_Next_Named_Actual
(N : Node_Id; Val : Node_Id); -- Node4
V7 : Node_Kind;
V8 : Node_Kind) return Boolean;
+ function Nkind_In
+ (T : Node_Kind;
+ V1 : Node_Kind;
+ V2 : Node_Kind;
+ V3 : Node_Kind;
+ V4 : Node_Kind;
+ V5 : Node_Kind;
+ V6 : Node_Kind;
+ V7 : Node_Kind;
+ V8 : Node_Kind;
+ V9 : Node_Kind) return Boolean;
+
pragma Inline (Nkind_In);
-- Inline all above functions
(1 => False, -- unused
2 => True, -- Left_Opnd (Node2)
3 => True, -- Right_Opnd (Node3)
- 4 => False, -- unused
+ 4 => True, -- Alternatives (List4)
5 => False), -- Etype (Node5-Sem)
N_Not_In =>
(1 => False, -- unused
2 => True, -- Left_Opnd (Node2)
3 => True, -- Right_Opnd (Node3)
- 4 => False, -- unused
+ 4 => True, -- Alternatives (List4)
5 => False), -- Etype (Node5-Sem)
N_Op_And =>
pragma Inline (Component_Items);
pragma Inline (Component_List);
pragma Inline (Component_Name);
+ pragma Inline (Componentwise_Assignment);
pragma Inline (Condition);
pragma Inline (Condition_Actions);
pragma Inline (Config_Pragmas);
pragma Inline (Constraints);
pragma Inline (Context_Installed);
pragma Inline (Context_Items);
+ pragma Inline (Context_Pending);
pragma Inline (Controlling_Argument);
pragma Inline (Conversion_OK);
pragma Inline (Corresponding_Body);
pragma Inline (Is_Component_Right_Opnd);
pragma Inline (Is_Controlling_Actual);
pragma Inline (Is_Dynamic_Coextension);
+ pragma Inline (Is_Elsif);
pragma Inline (Is_Entry_Barrier_Function);
pragma Inline (Is_Expanded_Build_In_Place_Call);
pragma Inline (Is_Folded_In_Parser);
pragma Inline (Name);
pragma Inline (Names);
pragma Inline (Next_Entity);
+ pragma Inline (Next_Implicit_With);
pragma Inline (Next_Named_Actual);
pragma Inline (Next_Pragma);
pragma Inline (Next_Rep_Item);
pragma Inline (Set_Component_Items);
pragma Inline (Set_Component_List);
pragma Inline (Set_Component_Name);
+ pragma Inline (Set_Componentwise_Assignment);
pragma Inline (Set_Condition);
pragma Inline (Set_Condition_Actions);
pragma Inline (Set_Config_Pragmas);
pragma Inline (Set_Constraints);
pragma Inline (Set_Context_Installed);
pragma Inline (Set_Context_Items);
+ pragma Inline (Set_Context_Pending);
pragma Inline (Set_Controlling_Argument);
pragma Inline (Set_Conversion_OK);
pragma Inline (Set_Corresponding_Body);
pragma Inline (Set_Is_Component_Right_Opnd);
pragma Inline (Set_Is_Controlling_Actual);
pragma Inline (Set_Is_Dynamic_Coextension);
+ pragma Inline (Set_Is_Elsif);
pragma Inline (Set_Is_Entry_Barrier_Function);
pragma Inline (Set_Is_Expanded_Build_In_Place_Call);
pragma Inline (Set_Is_Folded_In_Parser);
pragma Inline (Set_Name);
pragma Inline (Set_Names);
pragma Inline (Set_Next_Entity);
+ pragma Inline (Set_Next_Implicit_With);
pragma Inline (Set_Next_Named_Actual);
pragma Inline (Set_Next_Pragma);
pragma Inline (Set_Next_Rep_Item);
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